Fetal anemia as a consequence of hemorrhage into an ovarian cyst.

Fetal ovarian cysts are usually benign in nature and resolve spontaneously. Complications such as torsion and rupture have been described previously. A case of presumptive spontaneous hemorrhage into a fetal ovarian cyst is presented. Serial ultrasound and Doppler assessments revealed the development of fetal anemia, which was managed by intrauterine blood transfusion.